Meadow Walker took time on Tuesday to pay tribute to her father, the late Paul Walker, on what would have been his 44th birthday.

The 18-year-old model shared an adorable throwback on Instagram of the two dancing when she was just a toddler, and promoted the Paul Walker Foundation Do Good Challenge, encouraging her followers to do a random act of kindness and nominate others to do the same.

"In honor of my dad's birthday today, we're challenging you to DO GOOD!" Meadow wrote. "Share a video or photo of your random act of kindness and nominate 4 people to join the challenge! Be sure to tag the foundation as well as hashtag #PWFdogoodchallenge, so we can check out all of your posts!"

Meadow called out the late actor's close friend and Fast and Furious co-star, Vin Diesel, to do the challenge, and Diesel shared his own touching tribute in honor of Paul's birthday on Tuesday. Sharing an adorable flashback photo of Paul holding his daughter Hania on Instagram, Diesel also noted that he was "proud" of Meadow.

"Happy birthday Pablo... You have and are still changing the world," he wrote. "Your love lives through all whom have had the great fortune to know you. Meadow graduated this summer... made us all so proud. She is even building a foundation in your name to help the world. Would you believe Cody [Paul's brother] is in Houston continuing the work you were so passionate about... Remember when we were in Haiti and you asked me what the name should be... and now @reachoutww is realizing the dream. All the angels miss you... I miss you."